Field of the Invention and Related Art
The present invention relates to a process cartridge removably mountable in an electrophotographic image forming apparatus, a method for joining a developing means holding frame and a developer holding frame, and a flexible sealing member.
Here, an electrophotographic image forming apparatus is an apparatus that forms an image on a recording medium with the use of an electrophotographic image-formation method. As examples of an electro-photographic image forming apparatus, there are an electrophotographic copying machine, an electrophotographic printer (for example, a laser printer, an LED printer, and the like), a facsimile machine, a word processor, and the like.
A process cartridge is a cartridge that integrally comprises a charging means, a developing means or a cleaning means, and an electrophotographic photosensitive drum, and is removably mountable in the main assembly of an image forming apparatus. It also refers to a cartridge that integrally comprises a minimum of one means among a charging means, a developing means, and cleaning means, and an electrophotographic photosensitive drum, and is removably mountable in the main assembly of an image forming apparatus, and refers to a cartridge that integrally comprises a minimum of a developing means, and an electrophotographic photosensitive drum, and is removably mountable in the main assembly of an image forming apparatus.
As the cumulative usage of an electrophotographic image forming apparatus increases, it becomes necessary to carry out various maintenance operations, for example, replacing a photosensitive drum, replenishing a developing apparatus with developer, replacing the developer, adjusting a charging device, cleaning of a cleaning means container, and the like.
Thus, a process-cartridge system is employed by an electrophotographic image forming apparatus that employs an electrophotographic image-formation process. According to a process-cartridge system, an electrophotographic photosensitive member, and a single or a plurality of processing means, which act on the electrophotographic photosensitive member, are integrated in the form of a cartridge removably mountable in the main assembly of an image forming apparatus. A process-cartridge system makes it possible for a user to maintain an electrophotographic image forming apparatus without relying on service personnel, remarkably improving an electrophotographic image forming apparatus in operational efficiency Therefore, a process-cartridge system is widely used in the field of an image forming apparatus.
Referring to FIG. 33, a conventional process cartridge 85 comprises a development unit and a cleaning unit, which are joined with each other with the use of connecting pins 89. The development unit comprises a developing means container 83 and a toner container 86, which are welded to each other by ultrasonic welding. The developing means container 83 supports developing members such as a development roller. The cleaning unit comprises a photosensitive drum 11, a charge roller 12, a cleaning blade 14, a cleaning means container 87, and the like. The photosensitive drum 11, the charge roller 12, the cleaning blade 14, and the like, are supported by the cleaning means container 87. Further, a pair of compression springs 82 are placed in a compressed state between the cleaning means container 87 and developing means container 83, keeping the photosensitive drum 11 and development roller 18 pressed toward each other.
The developing means container 83 and toner container 86 are solidly joined to each other with the use of ultrasonic welding, thermal welding, adhesive, or the like. The solidly joined combination of the developing means container 83 and toner container 86 is connected to the cleaning means container 87, which doubles as a removed toner container, in such a manner that the combination can move relative to the cleaning means container 87, in other words, can pivot about the connecting pin 89. There are spacer rings (unshown) between the peripheral surfaces of the photosensitive drum 11 and development roller 18 to keep a proper amount of a gap between the peripheral surfaces of the photosensitive drum 11 and development roller 18. In other words, while the photosensitive drum 11 and development roller 18 are kept pressed toward each other in a manner to pivot about a line connecting the axial lines of the connecting pins 89, the spacer rings keep the proper amount of gap between the photosensitive drum 11 and development roller 18.
There is a tendency that in order to extend the process-cartridge replacement interval, in other words, in order to extend the length of the service life of a process cartridge, a toner container (developer container) and a removed toner container are increased in capacity.
As a toner container is increased in capacity with the use of any of the conventional technologies, the amount of developer (toner) filled in the toner container increases, which results in an increase in the amount of the load which is applied to the spacer rings and also in the amount of the load which is applied to the development roller 18 and photosensitive drum 11.
The primary object of the present invention is to provide a method for connecting a developing means frame and developer holding frame in such a manner that the two frames are movable relative to each other; a developing apparatus, which comprises a developing means frame and a developer holding frame, which are movable relative to each other; a process cartridge; and a flexible sealing member suitable for using the connecting method.
Another object of the present invention is to provide a method for connecting a developing means frame and a developer holding frame in such a manner that the load which is applied to a developing member and an electrophotographic photosensitive member does not fluctuate in response to the amount of the developer; a developing apparatus and a process cartridge, in which the load which is applied to a developing member and an electrophotographic photosensitive member does not fluctuate in response to the amount of the developer; and a flexible sealing member suitable for the connecting method.
Another object of the present invention is to provide a method for connecting a developing means frame and a developer holding frame in such a manner that the load which is applied to a developing member and an electrophotographic photosensitive member does not increase even if the amount of the developer stored in the developer holding frame increases; a developing apparatus and a process cartridge, in which a developing means holding frame and a developer holding frame are connected to each other in such a manner that the two frames are movable relative to each other; and a flexible sealing member suitable for the connecting method.
Another object of the present invention is to provide a method for connecting a developing means frame and a developer holding frame in such a manner that the load which is applied to a developing member and an electrophotographic photosensitive member does not increase even when the developer container is increased in capacity, and also that the load which is applied to a developing member and an electrophotographic photosensitive member does not change even when the amount of the developer within the developer container decreases; a developing apparatus and a process cartridge, which comprise a developing means frame and a developer holding frame, which are connected to each other with the use of the connecting method; and a flexible sealing member suitable for the connecting method.
Another object of the present invention is to provide a developing apparatus and a process cartridge, in which a flexible seal is folded so that the first and second holes of the flexible sheet align with each other, and the two halves of the flexible sheet created by the folding are pasted to each other at their edges.
These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings.
FIG. 1 is a vertical sectional view of an electrophotographic image forming apparatus.
FIG. 2 is a vertical sectional view of a process cartridge.
FIG. 3 is a front view of the process cartridge.
FIG. 4 is a rear view of the process cartridge.
FIG. 5 is a perspective view of the process cartridge as seen from diagonally above the top right of the rear end of the process cartridge in terms of the direction in which the process cartridge is mounted.
FIG. 6 is a perspective view of the process cartridge as seen from diagonally below the bottom right of the front end of the process cartridge in terms of the process-cartridge mounting direction.
FIG. 7 is an exploded perspective view of the process cartridge.
FIG. 8 is a rough rear view of the process cartridge, with the side cover removed.
FIG. 9 is a rough front view of the process cartridge, with the side cover removed.
FIG. 10 is a perspective view of a sealing sheet for sealing between a toner container and a developing means holding frame, and components related to the sealing sheet.
FIG. 11 is a perspective view of a sealing sheet for sealing between a toner container and a developing means holding frame, and components related to the sealing sheet.
FIG. 12 is a perspective drawing for depicting how the sealing sheet is applied.
FIG. 13 is a perspective drawing for depicting how the sealing sheet is applied.
FIG. 14 is a perspective drawing for depicting how the sealing sheet is applied.
FIG. 15 is a perspective drawing for depicting how the sealing sheet is applied.
FIG. 16 is an exploded perspective view of the process cartridge, for showing the sealing sheet for sealing between a toner container and a developing means holding frame in another embodiment of the present invention.
FIG. 17 is a vertical sectional view of the process cartridge, for showing the sealing sheet for sealing between a toner container and a developing means holding frame in another embodiment of the present invention.
FIG. 18 is an exploded perspective view of a developing apparatus, for describing the structure for connecting a developing means holding frame and a cleaning means holding frame.
FIG. 19 is a perspective view of a portion of the developing apparatus.
FIG. 20 is an exploded perspective view of the structure for connecting the developing apparatus and cleaning means holding frame.
FIG. 21 is a perspective view of the structure for connecting the developing apparatus and cleaning means holding frame.
FIG. 22 is a rear view of the structure for connecting the developing apparatus and cleaning means holding frame.
FIG. 23 is an exploded perspective view of the developing means holding frame and side cover, for showing their relationship.
FIG. 24 is a perspective view of the couplings for driving the photosensitive drum.
FIG. 25 is a rear view of the couplings for driving stirring members.
FIG. 26 is a rear view of the couplings for driving stirring members.
FIG. 27 is a diagram of the system for driving the process cartridge.
FIG. 28 is a front view of a cooling means of the process cartridge.
FIG. 29 is a front view of the cooling means of the process cartridge.
FIG. 30 is a sectional view of a gear with an impeller at a plane Axe2x80x94A in FIG. 31.
FIG. 31 is a perspective view of the gear with an impeller.
FIG. 32 is a perspective view of the gear with an impeller at a plane Bxe2x80x94B in FIG. 31.
FIG. 33 is a vertical sectional view of an example of a conventional process cartridge.
FIG. 34 is a front view of a portion of the process cartridge, with the side cover removed.
FIG. 35(a) is a perspective rear view of a connecting member, and FIG. 35(b) is a perspective front view of the connecting member.
FIG. 36 is an exploded perspective view of the development roller, the development roller bearing, and components adjacent thereto, of the process cartridge.
FIG. 37 is a sectional view of the structure for supporting the development roller and the photosensitive drum, at one of the longitudinal ends of the process cartridge.
FIG. 38 is a perspective view of the connecting member in another embodiment of the present invention.
FIG. 39 is a front view of the cartridge mounting portion of an image forming apparatus.
FIG. 40 is a front view of the image forming apparatus, for showing the manner in which the process cartridge is mounted into or dismounted from the main assembly of the image forming apparatus.
FIG. 41 is a front view of the image forming apparatus, for showing the manner in which the process cartridge is mounted into or dismounted from the main assembly of the image forming apparatus.
FIG. 42 is a perspective view of the cartridge mounting portion of the image forming apparatus main assembly.
FIGS. 43(L), 43(M), and 43(N) are plan views for showing the manner in which the process cartridge is inserted into the image forming apparatus main assembly.
FIGS. 44(H), 44(I), and 44(J) are sectional drawings for showing the relationship among the guiding portion of the process cartridge, and the vertical movement lever and guide rail of the image forming apparatus main assembly.
FIGS. 45(P), 45(Q), and 45(R) are plan views for showing the manner in which the process cartridge is inserted into the image forming apparatus main assembly, in another embodiment of the present invention.
FIG. 46 is a side view of the vertical movement lever and the process cartridge, for showing the loci of the essential portions of the process cartridge, in the cartridge mounting portion.
FIG. 47 is a plan view of the process cartridge.
FIG. 48 is a bottom view of the process cartridge.
FIG. 49 is an exploded perspective view of the sealing member (sealing sheet) in another embodiment of the present invention, for showing a method for forming the sealing member.
FIGS. 50 and 51 are a perspective view of a sealing member (sheet) in an embodiment and a side view of a sealing member (sheet) in an embodiment, for showing the method for forming the sealing member.